Circuit interrupter



J. L. COTTER CIRCUIT INTERRUPTER Nov. 2,1, 1944.

Filed Dec. 26, 1942 Fgl ngz

Petenied Nov. 21, 1944 CIRCUIT INTERRUPTEB James L. Cotter, Wilkinsburg, Pa., assigner to Westinghouse Electric a Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application December 26, 1942, Serial No. 470,183

(Cl. 20o-163) 13 Claims.

This invention relates generally to electric'circuit interrupters, and more specifically to indoor disconnect switches. Switches of this type are usually mounted on panels or in enclosures where space and safety considerations are importantv factors. Y

Accordingly, one object of this invention is to provide a novel type of disconnect switch which requires a minimum of space in operation, yet is capable of introducing a safe air gap in the circuit.

Another object of this invention is-to provide a novel form of disconnect switch wherein al1 the live parts thereof are enclosed and inaccessible at least in the open circuit position of the switch.

Still another object of this invention is to provide a novel form of disconnect switch wherein at least the contacting parts of the switch are enclosed and inaccessible at al1 positions of the switch.

A further object-of this invention is to provide a novel switch of the type described having safety enclosure means for the live parts of the switch gang operated switch construction having novel Imeans insulating each switch to permit the switches to =be assembled in closely spaced relation.

Another object of this invention is to provide a novel gang operated switch construction with each switch arranged so as to require but a relatively small space for operation, and further arranged so that it may be safely assembled closely adjacent another switch.

These and other objects of this invention will become apparent upon consideration of the following detailed description of a preferred embodiment thereoiwhen taken in connection with the attached drawing, in which:

Figure 1 is a substantially central sectional view through a disconnecting switch embodying this invention; and -f Fig. 2 is a rear elevation of an assembly of three switches like the switch of Fig. 1, with the central switch shown in transverse section taken substantially o n the line II-II of Fig. l.

in a group of vthree for gang operation on a three phase circuit. The switches may be supported from a pair of metal supporting panel plates,

:such as an upper panel supporting plate 2 and a lower panel supporting plate 4. Each switch includes a pair of tubes 6, preferably of'a molded insulating material to house each of the contacts of the switch, and each tube is provided with an integral outwardly extending flange 8 at one end thereof, to be secured, as by 'bolts I2, to supporting panels 2 and 4, and to an intermediate spacer plate 9, also of insulating material. Securing bolts I2 may also serve to secure a cover I0 to the adjacent end of each insulating ytube 6.

Each insulating tube 6 is provided with a partition I4 intermediate the ends thereof which maybe molded integral with the tube as shown, to form a contact chamber I5, and a terminal chamber Il within the tube. A male contact member I6 is positioned within the contact chamber I5, and is formed integral with a threaded stud I8 threadedly mounted in a threadedaperture provided in partition wall I4. A lock nut 20 is provided on stud I8 to secure contact I6 in adjusted position, and a securing nut 24 is provided on stud I8 in terminal chamber I1 for clamping a conductor 22 against a washer 23, to electrically connect the conductor and stud. Con.. ductor 22 may extend out .the open end of terminal cham-ber Il, or as shown, laterally out through a side opening in tube 6.

The disconnectingswitch constituting this inl vention is illustrated on the drawing, arranged Each tube 6 is provided with a longitudinally extending slot 26 in the wall of contact chamber I5, which slot terminates at a point spaced from partition I4. A contact bridging member 28 is adapted to extend across the space between tubes 6 of each switch with its opposite ends extending through slots 26 into contact chambers I5, respectively. Bridging member 28 may or may not be provided with a jacket 30 of insulating material, preferably an insulating material which is molded directly thereon, in order to completely enclose all live parts, at all positionsy of the switch. Each bridging member 28 is provided with a plurality of insulating pins 32 and 32' extending therethrough, with the intermediate pin 32 provided for securing an operating rod 33 to the bridging member. The operating rod 33 is slidably mounted through an aperture provided in insulating spacer plate 9, and has the inner end forked for snugly receiving bridging member 28 so .that the operating rod and bridging member are rigidly connected when intermediate pin 32 is in place. Upper and lower insulating guide pins 32 on each bridging member are located admovement longitudinally of tubes 6.

jacent tubes 6 respectively, of each switch, and may, if desired, be provided with rollers or other means 34 on opposite ends thereof for engagement with tubes 6 at opposite sides of slots 26. The rollers 34 will, in conjunctionwith the slidable mounting of operating rod 33, act to guide bridging member 28 for rectilinear reciprocating The OP- erating rod 33 of each switch is adapted to be actuated by an actuating crank arm 50 having a slot 54 in the outer end thereof for receiving a pin 35, in the outer end of each rod 33. Each actuating crank arm 50 is mounted at the other end thereof on a square portion of a common actuating shaft 48 which extends transversely across the front of all the switches. Actuating shaft 48 may be rotatably mounted in spaced bearing brackets 56 (only one of which is shown), supported from lower supporting plate 4. The bearing portions of the shaft 48 may be rounded as shown at 58 for reception in bearings 68, of bearing brackets 56.

A female contact member 36 generally tubular in form, is adapted to be mounted on each end of each bridging member 28 within contact chambers I 5. Contact members 36 are slotted at one end to fit over the ends of bridging member 28 to be secured thereto in any desired manner, such for example, as by welding, brazing or the like. The projecting end of each contact member 36 is provided with a plurality of closely spaced, longitudinally extending slots 38 to provide a plurality of radially movable contact fingers 48, for telescoping engagement; with each contact member I6. Preferably, a pair of annular coil springs 42 are provided about contact fingers 48, suitably seated in peripheral grooves therein to resiliently press the contactngers into engagement with contact members I6.

Each bridging member 28 is provided within contact chambers I on the side thereof opposite contact members 36, with indicator projections 44 of insulating material, which may be secured to the bridging member in any desired manner,

such for example, as by riveting or the like. Indicator members 44 are in alignment with apertures 45 provided in tube covers I 8, so that upon movement of the bridging member out of engagement with contact members I6 to an open circuit position, indicator projections 44 will be projected through apertures 45 to give an indication at the front of the supporting' panels, of the open circuit or not.'

conditionof the switch. In order to provide a view of the air gap between bridging member 28 and contact members I6,when the switch is in open position, insulating tubes 6 may be provided with sight slots 4'6. By virtue of sight slots 46, the air gap between bridging member 28 and contact member I6 may be seen by an observer at the rear of the supporting panels- Slots 26 and 46, as Well as aperture 45, should be made small enough that it is impossible for a person to insert a finger to the interior of tubes 6, to thereby prebetween the switches.

ing member 28 is arrested by engagement with spacer plate 9. This is the open circuit position of the switches, and indicator projections 44 will extend through cover openings 45 so as to furnish an indication at the front of the supporting panels. Also as described above, the air gap between contact members 36 and I6 may be observed through sight slots 46. In the open position Aof the switches, bridging members 28 are electrically dead, and consequently, all live parts of the circuit will be enclosed within insulating tubes 6, whether insulating jacket 30 is employed When insulating jacket 30 is employed. all live parts of the switches will then be enclosed in insulation when the switches are moved to the closed circuit position shown in Fig. 1. It should benoted that the connections to the switches are made in chambers which are separated from the switch contacts by an insulating partition I4. Another feature of the invention is the inherent stability of the reciprocating bridging member due to guide rollers 34 and the guides for operating rod 33 formed by spacer plate 9.

Because the switch described herein is of the double break type, it will obviously require less space in the direction of movement of the blade than switches of the single break type. Moreover, because of the novel insulating enclosures for the live parts of each switch, it is possible to assemble the switches much closer together than would otherwise be possible. It will be noted that the tubes of insulation enclosing the switch contacts will act to laterally confine any arcs drawn when the switches are open, to prevent arcing Consequently, switches of the type described, when assembled for gang operation will require less space in two different directions than conventional types of switches.

Having described a preferred embodiment of the invention in vaccordance with the patent statutes, it is desired that the invention be not limited to this particular embodiment, because iL will be obvious to the persons skilled in the art that many modifications and changes may be made therein without departing from the broad spirit and scope of this invention and dened in the following claims.

I claim as my invention:

1. In a switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubularmeans extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, and the extent of movement of said bridging means being limited so that the ends thereof are retained in said tubular means at all positions of said bridging means.

2. In a' switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, at least the portion of said bridging means in the space between said tubular means having a covering of insulating material, and the extent of movement of said bridging means being limited so that the ends thereof are retained in said tubular means at all positions of said bridging means.

3. In a switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, and the outer ends of said tubularmeans having stop means secured thereto for limiting movement of said bridging means away from said contacts.

4. In a switch, spaced contacts, tubular means of insulating material telescoped over` each contact. and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, and the outer ends of sai tubular means being closed. f

5. In a switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, means limiting movement of said bridging means away from said contacts an amount less than the extent of said tubular means, and indicating means adapted to be projected from the outer end of at least one of said tubular means in response to movement of said bridging means to open circuit position.

6. In a switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts, the extent of movement of said bridging means being limited so that the ends thereof are retained in said tubular means at all positions of said bridging means and a side slot in at least one of said tubular means' so that at the open circuit position the air gap between said contacts and bridging means is readily visible. 7. In a switch, spaced contacts, tubular means of insulating material telescoped over each contact and extending outwardly thereof, confronting slots in said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therealong into and out of bridging engagement with said contacts', and -guide means on said bridging means adjacent opposite ends thereof for engagement with said tubular means adjacent said slots, to guide said bridging means in its movement.

8. In afswitch, contact means, tubular means of insulating material telescoped over said contact means and extending outwardly'thereof, a longitudinally extending slot in said tubular means, a switch blade having an end projecting into said slot, said blade mounted for movement or said end thereof substantially longitudinally or Y of said tubular means.

ysaid tubular means into and out of engagement with said contact means, and the movement of said switch blade being limited to not more than the extent of said tubular means.

9. In Va switch, contact means, tubular means of insulating material telescoped over said conmovement of said end of said blade in a direction away from said contact means an amount less than the extent of said tubular means.

10. In a switch, contact means, tubular means of insulating material telescoped over said contact means and extending outwardly thereof, a longitudinally extending slot in said tubular means, a switch blade having an end projecting into said slot, said blade mounted for movement of said end thereof longitudinally of said tubular means into and out of engagement with said contact means, and the outer end of said tubular means being closed for limiting movement of said end of said blade in a direction away from said contact means an amount less than the extent of said tubular means.

11. In a switch, contact means, blade means mounted for movement into and out of engagement with said contact means, a tubular member of insulating material receiving said contact means and a portion of said blade means, said tubular member extending in the path of movement of said portion of said blade member. said tubular member secured to one ofsaid means and having a slot for permitting relative movement or the other, and the movement of said switch blade means being limited to not more than the extent 12. In a switch, spaced contacts, tubular means vof insulating material telescoped over each contact and extending outwardly thereof, a slot in each of said tubular means extending longitudinally thereof, bridging means having opposite ends extending into said slots for movement therepositions of said bridging means.

13. In a switch, contact means, tubular means of insulating material telescoped over said contact means and extending outwardly thereof, a longitudinally extending slot in said tubular means, a switch blade having an end projecting into said slot, said blade mounted for movement of said end thereof substantially longitudinally o! said tubular meansninto and out of engagement with. said contact means, and guide means on said blade adjacent said one end thereof for engagement with said tubular means adjacent said slot to guide said blade in its movement.

JAMES L. CO'I'I'ER. 

